Fit an irrigation system

Hi, I'm looking to get quotes for the following jobs - Removing a section of large shrubs - L shaped raised bed with 3 tiers, made from concrete blocks which will need rendered and stone capping. Roughly 4.5m (length of the L) x 4m (bottom of the L) x 1m wide (i.e. width of the planter/"thickness" of the L). Tiering heights of 20cm, 40cm & 60cm. - Hedge trimming

Our insinkerator waste disposal unit [14 years old] has jammed. I've followed the online video using the unjamming tool, removed the unit from under the sink, re-fitted it but it still jams and trips the fuse. So conclusion is that it is a mechanical not electrical or plumbing, the grinding mechanism is at fault. Can you help?